The present invention relates to an eye characteristic measuring apparatus where when optical characteristics of an eye are measured, a difference component from relation with measured data in a reference optical path is taken whereby measurement in high accuracy is performed, and particularly the measuring apparatus is provided with a reference optical system separate from a measurement light receiving system.
Measurement results of the eye characteristic measuring apparatus include both aberration of an eye and aberration of the measuring apparatus. Consequently in order to cancel aberration of equipment, measurement has been performed using an article to be measured without aberration previously.
In the above-identified conventional method, however, since data measured at the initial stage are used, a problem exists in that the measured aberration is included in strain of the equipment produced later or aberration of the equipment caused by deformation due to temperature.
Accordingly appearance of such an eye characteristic measuring apparatus has been desired strongly as aberration during the measurement can be removed completely and quite exact measurement can be performed.
The present invention consists in an eye characteristic measuring apparatus, where a reference optical system illuminates a small region on the opposite surface of the reference reflecting article by the luminous flux from the first light source, and receives the luminous flux reflected and returned from the reference reflecting article. The first conversion member divides the reflection luminous flux received in the measurement optical system and/or the reference optical system into a plurality of beams, the first light receiving unit receives the plurality of beams divided in the conversion member, and the changing unit guides the luminous flux in the measurement optical system and the reference optical system alternately to the first light receiving unit. The arithmetic control unit can estimate the optical characteristics of the eye based on the receiving position of the luminous flux from the measurement optical system obtained in the first light receiving unit and the receiving position of the luminous flux from the reference optical system. Therefore the present invention has quite excellent effects that the aberration during the measurement can be removed completely and quite exact measurement can be performed.